bpf, arm64: Fix bpf trampoline instruction endianness
The sparse tool complains as follows: arch/arm64/net/bpf_jit_comp.c:1684:16: warning: incorrect type in assignment (different base types) arch/arm64/net/bpf_jit_comp.c:1684:16: expected unsigned int [usertype] *branch arch/arm64/net/bpf_jit_comp.c:1684:16: got restricted __le32 [usertype] * arch/arm64/net/bpf_jit_comp.c:1700:52: error: subtraction of different types can't work (different base types) arch/arm64/net/bpf_jit_comp.c:1734:29: warning: incorrect type in assignment (different base types) arch/arm64/net/bpf_jit_comp.c:1734:29: expected unsigned int [usertype] * arch/arm64/net/bpf_jit_comp.c:1734:29: got restricted __le32 [usertype] * arch/arm64/net/bpf_jit_comp.c:1918:52: error: subtraction of different types can't work (different base types) This is because the variable branch in function invoke_bpf_prog and the variable branches in function prepare_trampoline are defined as type u32 *, which conflicts with ctx->image's type __le32 *, so sparse complains when assignment or arithmetic operation are performed on these two variables and ctx->image. Since arm64 instructions are always little-endian, change the type of these two variables to __le32 * and call cpu_to_le32() to convert instruction to little-endian before writing it to memory. This is also in line with emit() which internally does cpu_to_le32(), too. Fixes: efc9909f ("bpf, arm64: Add bpf trampoline for arm64") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Link: https://lore.kernel.org/bpf/20220808040735.1232002-1-xukuohai@huawei.com
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